This invention generally relates to the art of optical fibers and, particularly, to an optical fiber interconnection apparatus.
Fiber optics are being used in electronic systems with ever-increasing frequency and intensity, because optical fibers can transmit much greater quantities of information than electrical conductors. In increasing numbers of applications, an optical as well as electrical interconnection is desirable between circuit components. Electrical energy is translated to optical energy which is transmitted by an optical fiber or fibers between electronic components, such as printed wiring or circuit boards. One of the problems with using optical fibers is that they are extremely small and difficult to handle. A typical fiber may be an acrylic coated glass fiber having a total outside diameter of 250 microns. These tiny fibers are fragile and cannot withstand abrupt turns or the like. Consequently, it has become known to bond the fibers to flat flexible substrates to form what is called an optical backplane. The present invention is directed to improvements in optical fiber interconnection apparatus or backplanes to address the problems of handling or manipulating optical fibers in interconnection systems.
One type of optical interconnection apparatus includes a flat flexible body member defined by a peripheral edge. A plurality of optical fibers are mounted to the body member so that their ends extend beyond the peripheral edge, and the ends of a plurality of the fibers extend to different locations of the edge. The fibers are mounted to the body member by a pressure sensitive adhesive. A conformal coating is applied over the body member, adhesive and fibers, and the coating covers the ends of the fibers extending beyond the peripheral edge. The coating of the extending ends of the fibers results in the fibers becoming xe2x80x9cribbonizedxe2x80x9d, with the fibers being maintained in a plane by the coating. One of the problems with ribbonizing the fiber ends is that the fibers cannot adequately bend in the plane of their ribbonization. Another problem is that it is difficult to apply the coating to the fiber ends when they extend beyond the body member a considerable length. The present invention is directed to solving these further problems in optical fiber interconnection apparatus of the character described.
An object, therefore, of the invention is to provide a new and improved optical fiber interconnection apparatus.
In the exemplary embodiment of the invention, the apparatus includes a flat flexible body member having a peripheral edge. A plurality of optical fibers are mounted to the body member so their ends extend beyond the peripheral edge, and the ends of a plurality of the fibers extend to different locations of the edge. A tube member surrounds the ends of a selected plurality of the fibers extending beyond the peripheral edge from at least one of the different locations.
As disclosed herein, the flat flexible body member includes a projecting portion at least at one location. The selected plurality of fibers are mounted on the projecting portion and the ends of the fibers extend beyond an edge of the projecting portion. In one embodiment, a joining tube section is telescoped over the projecting portion and a proximal end of the tube member. This prevents breakage of the fibers at the edge of the projecting portion. In another embodiment, the proximal end of the tube member is positioned over the projecting portion to not only reinforce the tube member but to prevent breakage of the fibers at the edge of the projecting portion.
In a further embodiment of the invention, the extremities of the ends of the selected plurality of fibers are mounted to a guide member which is used to thread the fibers through the tube member. A joining tube section or a distal end of the tube member is positioned over at least an edge portion of the guide member over which the fibers extend. In still another embodiment of the invention, the tube member is slit lengthwise thereof to allow the selected plurality of fibers to be laid into the tube member.
Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings.